Torque converter



Jan. 9, 1940.

A. D. RoBBvlNs TORQUE CONVERTER Filed March 25, 1936 2 Sheets-Sheet 1 vf *L* bmw N Q 1 u //f.// QM, mM. @N NN r. ww \m.., mw v 1 m Mv hm. N ma m. w om. RK, W WN R, i m@ uw -l :if f v d x y /f l @n Y MWF Q, M7/ Nh l N Y A I l N Nm. v h# v mmm' n mum. .WT Nm, WN QN L-. QN an. N. MPN .Q YQ\ .mm m WT vw Jan. 9, 1940. A D RQBBWS 2,186,556

TORQUE CONVERTER Filed March 25, 1936 2 Sheets-Sheet 2 Patented Jan. 9, 1940 A. Y. 'l

UNITED STATES PATENT OFFICE .....U-...m ....ill'lf 4 Claims. (Cl. 6053) This invention relates to torque converters and ders 3 I arranged on a hub 32 which may be keyed the device is intended for use with a prime mover, to the shaft I1. A second series of pistons 33 such as an automobile engine,whereby the torque are fitted to the cylinders 3l. The pistons 33 of the prime mover, after being transmitted have spherical ends 34 adapted to engage an anthrough the. torque converter, may be changed nular track 35 mounted on flanges 33 and 31 6 to a greater torque at slow speed, or a low torque which are journaled in bearings 33 and 39. The at higher speed. bearings 33 and 39 are carried in a cradle 43 piv- Tne objects of the invention are to provide a otally mounted in the housing 23 by means of the torque converter in which the eiiiciency is relapin 4I.

tively high, as compared with previous construc- The cradle 43 may be oscillated by suitable 10 tions, and in which the torque or speed of the means andI may be positioned to hold the track output shaft may be changed while power is being 35 concentric with the shaft I1 or the track may transmitted. Y be held eccentric to the shaft on one side or the I attain these and other objects as will be apother. It will be seen that rotation of the shaft l5 parent as the invention is described in detail and I1 and cylinders 3I will tend to force the pistons l5 in connection with the 'accompanying drawings 33, by centrifugal force, against the track 35 and in which: the friction of the engaging ends 34, against the Figure 1 is a view in section on a vertical plane. track, will tend to rotate the track and nangesv Fig. 2 is a view in section on line 2-2 of Fig. 1. 35 and 31 in the anti-friction bearings 33 and 33.

Fig. 3 is a view in section on line 3-3 of Fig. 1. If the track is held eccentric to the shaft I1, Fig. 4 is a section on line 4-4 of Fig. 1. Figs. as shown in Fig. 2, rotation of the cylinders 3I 5 and 6 are also sections at line 4-4 to illustrate will cause the pistons 33 to be reciprocated and various positions of parts in operation. when the track is held concentric to the shaft Similar reference characters refer to similar I1, the cylinders 3| may be rotated without reparts throughout the several views. ciprocating said pistons. The cylinders 3|, pis- 2 5` Referring to Fig. 1, a driving shaft is indicated tons 33 and track 35 may, under certain condiat II to which power may be supplied by any tions hereinafter described, form a pump unit suitable source. The shaft has a flange I2 to which may be designatedas unit B. which a casing cover I3 is attached by bolts I4. The shaft I1 is formed with ports 42 and 43 A casing I5 is secured by bolts I6 to the cover connecting with passages 44 and 45 in said shaft 30 I3. The casing supports a hollow shaft I1 coas the track I3 causes the pistons 25 to reciproaxial with the driving shaft II and the casing cate twice for each revolution of said track in and shafts are adapted to rotate together, being relation to said cylinders,two each of passages 44 journaled on the bearings I8 and I9 supported and 45 are required to convey uid to or from in the housing 20. the cylinders 22. The cylinders 22 have inwardly 35 The shaft I1 has a conical projection 2l exextending openings 43 adapted to cooperate with tending within the casing I5 and supporting a the ports 42 and 43. As the cylinders 22 are rogroup of cylinders 22 lformed on a hub 23. f The tated about the conical projection 2|, the openhub has a conical seat 24 formed to seat on ings 45 will communicate with the ports 42 or the projection 2|. The cylinders 22 are fitted 43 and permit fluid to'flow to or from the cyl- 4,0

with pistons 25 adapted to force fluid toward the inders. center or hub 23. The pistons have slots 23 The shaft I1 carries a sleeve 41 in which are formed at their outer ends to receive rollers 21 passages 43 and 49. The sleeve has a. conical journaled on pins 23 which flt into holes 23 in end 53 adapted to form a close running fit with the forked ends of the pistons. The rollers ena conical seat 5I in the hub 32. The passages 45- gage an internal cam 33 within the casing I3. As 43 and 43 terminate in ports 5 2 and 53 which seenin Fig. 2, the form of the cam is substantially communicate with openings 55 in the cylinders 3l. oval and, in consequence, when the casing is ro- The sleeve 41 has an arm 56 which extends into tated in relation to the cylinders, the rollers 21 a slot 51 in the casing 20. The arm prevents the will be caused to move radially and reciprocate sleeve 41 from turning when the shaft I1 is ro- 50 the pistons twice for each revolution of the castated. ing. The cylinders, may under certain conditions, The hub 23 of the cylinders 22 is keyed to a hereinafter described, form a pump unit which shaft 53 extending through the hollow shaft I1. for future reference may be designated as unit A. The shaft 53 terminatesin a ange 53 to which 5;; The shaft I1 carries a second group of cylina driven shaft (not shown) may be attached. 55

The sleeve 41 has surfaces at 6I, 62 and 63 adapted to t annular surfaces on the shaft I1. Between the surfaces 6I and 62 is an annular recess 84 ln the sleeve 41. The recess communi- Cates with the passage 48 in the sleeve and said recess provides an outlet or inlet to the passage 44 in the shaft I1. Between the surfaces 62 and 63 an annular recess 65 is formed in the shaft I1. The recess 65 forms a connecting channel between the passages 45 and 49 in the shaft and sleeve, respectively. Therefore in any position and 'H in the Shaft I1.

of rotation of the shaft I1 there will be a continuous connection between the passages 44 and 48 also between the passages 45 and 49.

Rings 86, 61 and 68 are fitted in grooves 69, The rings are of the expanding type well known as piston rings, and serve to seal the surfaces 6|, 62 and 63 against loss of the fluid with which the cylinders and passages may be lled. It will be kseen -that the surfaces at 6I, 62 and 63 are of different diameters and when iiuid in either annular recess 64 or 65 is under hydrostatic pressure, a relative axial thrust will be set up between the shaft I1 and the sleeve 41. 'I'he shaft becoming, in effect, a dierential piston, due to the difference in diameters of surfaces 6I and 62 or 62 and 63. Axial thrust due to the above named cause will therefore thrust the shaft I1 toward the seat 24 in the hub 23 and the reacting thrust against the sleeve will thrust it toward the seat 5I on the hub 32.

Due to hydrostatic pressure in any of the ports or openings 46 or 55, there will be an axial thrust tending to force the conical surfaces 24 or 56 out of the seats 5I or 24. By choosing a suitable angle for the cones and making the surfaces 6I, 62 and 63 of suitable relative diameter, the thrust of the cones against their relative seats may be regulated in a manner which will insure keeping the cones and seats together and forming a relatively oil tight running joint between said cones and seats. In order to permit correct functioning of the conical surfaces and seats, the hub 32 is preferably made axially movable on shaft I1, so axial thrust from sleeve 41 may be conveyed through hub 32 bearing I9, shaft 56 and draw hub 23 against conical member 2|.

The action of the device may be understood by examining various operating conditions. For example, assuming the track 35 to be held concentric with the shaft I1, in this position rotation of the cylinders 3l will cause no reciprocation of the pistons 3:!V and there will be no pumping action in unit B. If the casing I3 is rotated under these conditions, fluid in the cylinders 22 will be under pressure due to cam 30 forcing the pistons 25 inwardly. There is, however, no escape forthe fluid from unit A, the pistons therefore cannot reciprocate, and the cylinders 22 and shaft 58 will be compelled to rotate with the casing I3 and at the same speed.

The track 35 may be moved to an eccentric position Where the stroke of the pistons 33 will cause unit B to equal pump unit A in capacity per revolution. In this position rotation of the casing I3 will not cause the cylinders of pump unit A to rotate but the pistons 25 will reciprocate and pump fluid through passages 45 and 49 to unit B and from unit B the iiuid will return to unit A through passages 48 and 44, assuming the direction of rotation as indicated by the arrows in Figs. 2 and 4, the amount of uid pumped by the pistons 25 into unit B being exactly equal to the amount of fiuid pumped by pistons 33 of unit B into unit A, whereby member 23 will re- I main stationary.

Fig. 4 shows the track 35 in a position half way between those mentioned and in which the unit B is vabout half the capacity of unit A. In this position rotation of the casing I3 will cause pressure on the pistons 25, as before, and uid will be forced to unit B. But, as unit B has now only half the capacity of unit A, the cylinders 22 of unit A will turn at half the speed of the casing I3. It will be noted that pressure from unit A will force fluid to the lower pistons of unit B and forcing said pistons toward track 35. The track at this point presents anangular surface to the end of the pistons 33 and the sides of the pistons will press against the walls of the cylinders at 15, tending to turn said cylinders in the same direction as the casing I3. It will therefore be seen that when fiuid is forced from unit A to pump B, and pump B is set at less capacity than unit A, pump B will become a motor, regenerating power and adding it to the torque of the driving member and thereby increasing the pressure of the uid in the compression side of the system. Any intermediate position of track 35 between those thus far shown may be used and any degree of speed from zero to direct drive may be obtained and the increase of torque in the driven member 22 is substantially in proportion to the decrease in speed.

Another condition is shown in Fig. 5 with track 35 displaced to the opposite side as compared to Fig. 4. In this position fluid in lower cylinders of unit B is forced back through passages 49 and 45 to unit A and will turn cylinders 22 of the driven member at a greater speed than the driving member I3.

Fig. 6 shows a condition in which the track 35 is displaced to give a greater capacity to the unit B than the capacity of unit A. In this position iiuid exhausted from unit B will cause pressure in passages 48 and 44 therefore causing unit A to turn the driven member 23.n the opposite direction to the driving member.

In all positions where the axis of the track 35 is eccentric to the shafts, the cradle 40 serves as a reaction member against which unit B, when operating as a motor, will react to increase torque or give reverse action.

Any loss of fluid, during operation, through leakage, may be replaced through inlets 16 or 11 in sleeve 41. Into said inlets fluid may be forced by a pump, which may be of any character and is not shown.

It will thus be seen that I have provided a relatively simple device capable of transmitting power in either direction at various speeds including faster than the driving member and at increased torque in the lower speeds. It will also be seen that provision has been made to guard against undue leakage and relativelyl high pressures may be used.

To oscillate the cradle and thereby change the 4conditions of drive I prefer to use a fluid operated piston 18 operating in a cylinder 19. Any

suitable pump may be used to force uid to said cylinder and said pump may be driven from the prime mover or the driven member.

It is intended that the above description and drawings shall be considered in an illustrative and not in a limiting sense, and many changes may be made without departing from the spirit of the invention as set forth in the following claims.

What *I claim is:

aisance 1. A power transmitting device comprising, in combination, a housing, a rotatable hollow shaft journaled in said housing, an internal cam track rotatably connected to said shaft, a series of radial cylinders united on a hub and in the plane of said track, a driven shaft rotatably mounted in said hollow shaft, said hub being keyed to said driven shaft, a ported projection on said hollow shaft extending within said hub, said cylinders having openings adapted to communicate with the ports in said projection, a second series of cylinders united on a hub and rotatively connected to said hollow shaft, pistons in said second series of cylinders, a laterally adjustable track movably mounted in said housing and engaging said second series of pistons, a nonrotatable sleeve supported by said hollow shaft and having a ported projection extending within said second series of cylinders, said second series ofcylinders having openings adapted to communicate with the ports of said sleeve, said sleeve and said hollow shaft having passages adapted to convey fluid from one series of cylinders to the other and a running joint between said sleeve and said shaft having recesses to convey fluid from said shaft to said sleeve.

2. A powertransmitting device as claimed in claim 1, in which the running joint comprises cylindrical surfaces at each side of said recesses and said surfaces being of different diameters to comprise a piston whereby pressure of the uid acts to force the ported surface of said sleeve against the hub of said second series of cylinders.

3. A power transmitting device comprising, in combination, a rotatable driving shaft, an internal cam track rotatably connected to said shaft, a driven shaft, a series of cylinders united on a hub and keyed to said driven shaft, pistons in said cylinders adapted to be operated by said cam track, a ported conical projection on said driving shaft extending within a conical seat in said hub, said cylinders having openings adapted to communicate with the ports in said projection, a second series of cylinders united on a hub and rotatively connected to said driving shaft, pistons in said second series of cylinders, a, laterally adjustable track movably mounted in said housing and engaging said second series of pistons, a nonrotatable sleeve supported by said driving shaft and having a ported conical end, the hub of said second series of cylinders having a conical seat adapted to receive the conical end of said sleeve, said second series of cylinders having openings adapted to communicate with ports in said sleeve, said sleeve and said driving shaft having passages adapted to convey iiuid from one series of cylinders to the other, a running joint between said sleeve and said driving shaft, annular recesses in said sleeve and said shaft to convey fluid from said shaft to said sleeve, and said running joint comprising cylindrical surfaces of different diameters whereby the conical end of said sleeve is forced into the conical seat of said second series of cylinders.

4. A structure as claimed in claim 3 in which means is provided to communicate the thrust of said sleeve through said driven shaft to draw the first named hub against the conical projection of said driving shaft.

AZOR D. ROBBINS. 

